1. Field of the Invention
The present invention relates to a mobile unit communication apparatus for communicating between mobile units such as a vehicle.
2. Description of the Related Art
A communication device for communicating between traveling vehicles and exchanging the information such as a traveling state of a vehicle is already disclosed in Japanese Patent Unexamined Publication No. Hei. 5-266399(JP-A-5-266399) for example. Such a conventional type communication device is provided with a radio communication device. The conventional type communication device transmits a radio signal including an information signal of an own vehicle by the radio communication device. Further, the conventional type communication device receives an information signal of another vehicle by the radio communication device, analyzes the received information signal of another vehicle and informs a driver and others of information required for the traveling of the own vehicle.
However, there is a case an obstacle such as the other vehicle exists between a vehicle transmitting an information signal and a vehicle receiving it because an information signal is transmitted as a radio signal. Thus, there is a problem that a radio signal is not received by the vehicle which should receive it even if the vehicle transmitting the information signal and the vehicle receiving it are near each other. Hence, the vehicle, which should receive it, continues traveling without acquiring required information of another vehicle.
The problem is caused not only in the case of a vehicle but in the case of a mobile unit such as a walker.